Final answer:
The lighter fragment of a shell that explodes will have a greater velocity than the heavier fragment, due to conservation of momentum.
Step-by-step explanation:
The question relates to the conservation of momentum in explosions, which is a concept in physics. When a shell explodes into two fragments and one fragment is 25 times heavier, the law of conservation of momentum states that the total momentum of both fragments combined must equal the momentum of the shell before explosion (assuming no external forces act upon them). Since momentum is the product of mass and velocity (p = mv), and the system is isolated, the two fragments must move in opposite directions with velocities inversely proportional to their masses to maintain the total momentum at zero as it was before the explosion. Therefore, the lighter fragment will have a velocity 25 times greater than that of the heavier fragment. In terms of the options provided: c) The velocity of the lighter fragment is greater.